This project is evaluating factors associated with drug users seeking treatment in a hospital emergency room. Drug users may present to a hospital emergency room for a variety of reasons, some clinically appropriate (e.g., a life-threatening medical consequence of drug use) and some less efficient uses of the health care system (e.g., non-urgent medical condition, attempt to enter substance abuse treatment). There is little data available on the relationship between emergency room visits by drug users and their seeking of and participation in drug abuse treatment. This study, in collaboration with the Department of Emergency Medicine at the Hopkins Bayview Medical Center, Baltimore, MD, collects data on the sociodemographic, drug use, and treatment-seeking behavior of an unselected series of drug users visiting an urban hospital emergency room. Another component in collaboration with the Clinical Dependency Unit at the Hopkins Bayview Medical Center, is evaluating the influence of medical co-morbidity and prior medical and substance abuse treatment on the response to short-term inpatient detoxification treatment for substance abuse.